Calnex LogoCalnex
AI Tools

AI Context Window Calculator

See how much content fits in the context window of major AI models. Convert between tokens, words, pages, and code files to plan your prompts and RAG chunks.

Parameters

Select the type of content to estimate.

For text: KB of text. For code: number of files. For pages: number of pages. For words: word count.

Results

Estimated Tokens12800

50 KB of plain text ≈ 12,800 tokens

Other results (1)
Model Compatibility
[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

Why Choose AI Context Window Calculator

Calculate how much content fits in the context window of GPT-4.5, Claude 3.5 Sonnet, Gemini 1.5 Pro, and other models. Convert between KB of text, code files, book pages, and word counts to plan prompts and RAG retrieval.

  • ✓Convert words, pages, code files, and kilobytes into AI tokens
  • ✓Compare context windows for major LLMs like GPT-4o, Claude 3.5, and Llama 3
  • ✓Optimize Retrieval-Augmented Generation (RAG) chunking strategies
  • ✓Determine which models can handle your entire codebase or document length

How to Use

  1. 1Select your input content type (Plain Text, Source Code, Book Pages, or Word Count)
  2. 2Enter the estimated amount (e.g., number of pages or code files)
  3. 3Review the calculated token estimate
  4. 4Check the Model Compatibility list to see which AI models can process your input

Frequently Asked Questions (FAQ)

What is an AI context window?

A context window is the maximum amount of text (measured in tokens) an AI model can process in a single prompt. This includes both your input prompt and the model's generated response.

How are code files estimated?

By default, we estimate that an average source code file contains around 200-300 lines of code, translating to a specific token density. Code generally consumes more tokens per word due to heavy use of symbols, punctuation, and camelCase variables.

Which models have the largest context windows?

Currently, models like Gemini 1.5 Pro offer up to 2 million tokens of context, capable of digesting entire books or massive codebases. Claude 3 models support 200k tokens, while GPT-4o supports 128k tokens.